BOEING 777 Hard Landing vertical G criteria

[1jz]

What is the G factor requiring hard landing checks by maintenance with aircraft being below max landing weight?

I saw an AMM chart that indicates 1.5 ish for the beginning of checks envelope.
Pertinent to mention that the note in the chart said something like this;

Load factor = Vertg + 1g

Anyone has references to elaborate the scenario?

[C152gal]

747 is 1,4g. Don't ask me how I know it.

[Highway1]

At Zero roll angle the G Factor is 1.2

Determination of a Hard Landing check is done by the Flight Crew. MM 05-51-01 P201

(2) The flight crew must make a determination if a hard landing has occurred.

I would give you a picture of the chart but as a newby I'm not allowed to post attachments - sorry

[1jz]

Ok.. so that means the Vertical G should just be at a value of 1.5 for maintenance checks?

Is not it a bit on the lower side?

Does the certification standard allow it?

[spannersatcx]

2.5g, as in 1.5+1 before you start the chpt 5 checks.

[Highway1]

Originally Posted by 1jz

Ok.. so that means the Vertical G should just be at a value of 1.5 for maintenance checks?

Is not it a bit on the lower side?

Does the certification standard allow it?

It depends on the Roll Angle - at Zero degrees role the Incremental load factor is 1.2. As you increase the roll angle the factor reduces to 0.6 at 6 degrees. Over 6 degrees the Load factor becomes irrelevant as a Part B inspection is mandatory.

[1jz]

Thank you every one..

Consider me as a newb for a while with this.

In simple terms, if the load factor (vertical G) is 1.2 G or so with zero roll angle. Does that suffice for the hard landing checks?

Or that would be at 2.2 G value?

[spannersatcx]

Originally Posted by 1jz

Thank you every one..

Consider me as a newb for a while with this.

In simple terms, if the load factor (vertical G) is 1.2 G or so with zero roll angle. Does that suffice for the hard landing checks?

Or that would be at 2.2 G value?

Not if the G required for the checks is 1.5 (2.5).

[Highway1]

Originally Posted by 1jz

Thank you every one..

Consider me as a newb for a while with this.

In simple terms, if the load factor (vertical G) is 1.2 G or so with zero roll angle. Does that suffice for the hard landing checks?

Or that would be at 2.2 G value?

It would be 2.2G - the incremental Load factor is the amount away from steady level flight (1G).

So at zero roll the threshold for a part B inspection is 2.2G declining to 1.6G at 6 degrees roll - anything over 6 degrees roll requires Part B inspection irrespective.

Hope thats clear

[1jz]

Thanks a lot.. well explained